Drift correction: using alternative button instead of spacebar?

Titus

Hello everyone,

we are using a custom built response box that has 3 buttons on it. These buttons produce number-keypresses as if it came from a keyboard: "1", "2", and "3". We are using the left and right button as answer buttons and have everything set to use "1"=no and "3"=yes.

However, we'd like to use the middle button that gives a "2" to trigger the successful drift correction in between trials.

I could not find a way to change the button that is the trigger to move on from the drift correction. Is there a way to do this or a workaround for the input "2" to be translated into a spacebar press?

Best,
Titus

sebastiaan

Hi Titus,

Drift correction is implemented differently for each eye tracker. So the main question is: which eye tracker are you using?

Cheers,
Sebastiaan

Titus

Hi Sebastiaan,

right, thanks for pointing that out. We are using the EyeLink 1000. Do you know how that would work on this model?

Best,
Titus

sebastiaan

Hi Titus,

In principle, I think this is hardcoded into the EyeLink software. That is, I don't think that you can convince the EyeLink to accept anything but a space bar for drift correction. However, you can trick the EyeLink software by feeding it a space bar when, in your case, a button was pressed.

To do so, you would need to edit the function EyelinkGraphics.get_input_key(), which is located in pygaze/_eyetracker/eyelinkgraphics.py. But this does not come with a manual, and you'd be treading into dark territories!

Cheers,
Sebastiaan

Titus

Hi Sebastiaan,
I'll look into this, thanks!
Best,
Titus